Genetic studies in schizophrenia are hampered by the complex heterogeneous clinical phenotype. Biological variables identified as trait markers of risk could clarify the mode of inheritance, define clinical subgroups and provide clues about aetiology.

To use single photon emission computed tomography (SPECT) to compare brain perfusion maps in patients with schizophrenia (n=19), their asymptomatic ‘high-risk’ relatives (n=36) and control subjects (n=34) and to examine the relationships between imaging, memory and P300 event-related potential.

SPECT, memory tests and P300 recording were carried out.

In the patients with schizophrenia and their relatives, perfusion was reduced in left inferior prefrontal and anterior cingulate cortex and increased bilaterally in a subcortical region. Perfusion significantly correlated with verbal memory and P300 amplitude in left inferior prefrontal cortex and with P300 latency in anterior cingulate cortex.

Medication– and symptom-free relatives had altered regional perfusion intermediate between subjects with schizophrenia and controls. Impaired perfusion, verbal memory and P300 appear to be related traits associated with an increased risk of illness.

People prescribed clozapine for treatment-resistant schizophrenia have mandatory haematological monitoring through a case register for identifying reversible neutropenia.

To quantify risk factors for agranulocytosis in subjects receiving clozapine.

Data from 12 760 subjects registered to receive clozapine from January 1990 to April 1997 were analysed. Risk factors for agranulocytosis were quantified using a Cox proportional-hazards regression analysis.

The risk for agranulocytosis in Asian subjects was 2.4 times that in Caucasians (P=0.03). There was an age-related increase in risk of 53% per decade (P=0.0001).

The case register yielded valuable information for guiding research into the causes of the haematological reactions.

The extent of suicide among addicts in the UK has not been sufficiently examined.

To examine suicide trends among registered addicts in the UK over a 25-year period.

We quantified suicide using International Classification of Diseases (ICD) external death codes E950–959, calculated annual age-standardised suicide rates, standardised mortality ratios (SMRs) and described trends in methods of suicide and drug overdose suicides in five successive cohorts of registered addicts.

Male and female suicide rates are 69.0 and 44.8 per 100 000 person-years, respectively. There was a consistent decline in suicide rate throughout the 25-year period. Among males, the SMR for suicide declined from 17.2 in 1968–1972 to 4.4 in 1988–1992 (SMR ratio=3.9, 95% CI=2.5–6.1); among females it declined from 52.6 to 11.3 in the same period (SMR ratio=4.7, 95% CI=1.9–10.8). Drug overdose was the most common method of suicide, accounting for 45% of cases. Significant increase in antidepressant (percentage difference=23.5%, 95% CI=15.2–31.8) and methadone (percentage difference=1.0%, 95% CI=0.5, 21.5) overdose in 1988–1992 compared with 1968–1972 was reported.

The findings confirm that addicts are still at higher risk of suicide than the general population and that prescribed drugs, notably antidepressants and methadone, influence this heightened risk.

Cognitive–behavioural therapy has been shown to be effective in reducing psychotic symptoms, but few patients have access to these services. Group cognitive treatment may provide a less costly service with similar benefits.

To explore the effectiveness of group cognitive–behavioural therapy on insight and symptoms, particularly auditory hallucinations.

Twenty-one DSM–IV diagnosed patients with schizophrenia with treatment-resistant, distressing auditory hallucinations were referred to a group programme consisting of six sessions of cognitive treatment following a strict protocol which emphasised individual power and control as well as coping strategies.

There were significant changes in all three main outcome measures following treatment; those changes were maintained at follow-up and were greater than changes over the waiting-list period. Specifically, there were changes in perceived power and distress as well as increases in the number and effectiveness of the coping strategies.

Group treatment for auditory hallucinations needs further investigation but does look promising and may provide a less costly alternative to individual cognitive treatment.

Several studies of papers published in non-psychiatric medical journals that report on randomised controlled trials (RCTs) indicate that there is inadequate reporting of the process by which randomisation is carried out.

To examine the adequacy of the reporting of the procedure of randomisation in clinical trials of parallel design published in the British Journal of Psychiatry (BJP) and the American Journal of Psychiatry (AJP).

All issues of the BJP and the AJP published between January 1990 and December 1998 were surveyed, and papers that reported on RCTs were examined to judge the adequacy of the reporting of the process of randomisation.

We found 183 papers which claimed to report on RCTs (73 in the BJP and 110 in the AJP). Nine (8.2%) of those in the AJP and six (8.2%) in the BJP described the technique of creating the randomisation sequence. Two (1.8%) of those in the AJP and 11 (15.1%) of those in the BJP described the mechanism of allocating treatment. One paper in the AJP and five papers in the BJP described both the generation of random numbers and allocation.

Adequate reporting of the method of randomisation was uncommon. The RCT status of some of the papers must therefore be in doubt.

The main psychotropic agent of the popular illicit drug ecstasy is 3,4-methylenedioxymethamphetamine (MDMA). In the light of animal studies and examinations of human cerebrospinal fluid, MDMA is suspected of causing neurotoxic lesions to the serotonergic system.

To postulate a relationship between ecstasy use and lasting alterations to the cerebral glucose metabolic rate.

Positron emission tomography (PET) with 2-[18F]-fluoro-2-deoxy-D-glucose (FDG) was performed on seven ecstasy users and seven subjects without any known history of illicit drug use. Data were compared for a limited number of brain regions.

By comparison with the control group, the glucose metabolic uptake of the ecstasy user group was altered within the amygdala, hippocampus and Brodmann's area 11

The results suggest the possibility that ecstasy use has lasting effects on central neuronal activity in humans.

Authors have suggested that the high rate of schizophrenia reported for African–Caribbeans living in the UK is due to misdiagnosis by British psychiatrists.

To compare the diagnoses made by a Black Jamaican psychiatrist with those of White British psychiatrists.

All in-patients on four wards at the Maudsley hospital were approached for the study; 66 participated: 24 White, 29 Black African–Caribbeans and 13 Blacks from other countries of origin. F. W. H., a Black Jamaican psychiatrist, conducted his standard clinical assessment and performed the Present State Examination (PSE) on these patients. His diagnoses were compared with the case note diagnoses made by British psychiatrists, and with the PSE CATEGO diagnoses.

Of 29 African and African–Caribbean patients diagnosed with schizophrenia, the diagnoses of the British and the Jamaican psychiatrists agreed in 16 instances (55%) and disagreed in 13 (45%). Hence, interrater reliability was poor (κ=0.45). PSE CATEGO diagnosed a higher proportion of subjects as having schizophrenia than the Jamaican psychiatrist did (χ2=3.74, P=0.052)

Agreement between the Jamaican psychiatrist and his UK counterparts about which patients had schizophrenia was poor. PSE CATEGO may overestimate rates of schizophrenia.

Positron emission tomography (PET) studies have revealed functional left superior temporal gyrus (STG) abnormalities in symptomatic schizophrenia during word generation.

To discover if this dysfunction is present in asymptomatic schizophrenia. To determine whether, without concurrent symptomatology, schizophrenia and bipolar affective disorder (BPD) are distinguishable by differing regional cerebral blood flow (rCBF) patterns during word generation.

A PETverbal fluency protocol was applied to six patients with BPD in remission and six patients with asymptomatic schizophrenia. Analysis included 10 control subjects from a contemporaneous study.

All groups showed relative reduction of rCBF in both superior temporal cortices. There were no quantitative differences in any group comparison. All groups exhibited negative covariation between rCBF in left prefrontal and right (but not left) temporal regions.

Abnormal patterns of left STG function cannot be regarded as a trait marker for schizophrenia. Functional abnormalities may reflect aspects of mental state.

There are no large published studies of the prevalence of seasonal affective disorder (SAD) among UK populations.

To determine the prevalence of SAD among patients attending a general practitioner (GP).

Patients aged 16–64 consulting their GPs in Aberdeen during January were screened with the Seasonal Pattern Assessment Questionnaire (SPAQ). SPAQs were also mailed to 600 matched patients, who had not consulted their GP during January. Surgery attenders who fulfilled SPAQ criteria for SAD were invited for interview to determine whether they met criteria for SAD in DSM–IVand the Structured Interview Guide for the Hamilton Rating Scale for Depression– Seasonal Affective Disorder Version (SIGH–SAD).

Of 6161 surgery attenders, 4557 (74%) completed a SPAQ; 442 (9.7%) were SPAQ cases of SAD. Rate of caseness on the SPAQ did not differ between surgery attenders and non-attenders. Of 223 interviewed SPAQ cases of SAD, 91 (41%) also fulfilled DSM–IVand SIGH–SAD criteria.

There is a high prevalence of SAD among patients attending their GPs in January in Aberdeen; this is likely to reflect a similar rate in the community.

Transcranial magnetic stimulation of the motor cortex may not only elicit excitatory responses in hand muscles contralateral to the stimulated hemisphere, but may also suppress tonic voluntary electromyogram activity in muscles ipsilateral to the stimulation. This inhibition is mediated between the motor cortices via the corpus callosum.

To investigate motor excitability and interhemispheric (transcallosal) connections in patients with schizophrenia.

Transcallosal inhibition and motor conduction parameters were investigated in ten patients with schizophrenia and in ten age- and gender-matched healthy subjects.

Transcallosal conduction time (TCT) and duration of the inhibition were significantly longer in patients with schizophrenia (mean (s.d.)): TCT, 12.4 (2.9) ms in normal subjects and 15.3 (2.6) ms in patients (P=0.03); mean duration, 34.1 (4.9) ms in normal subjects and 51.9 (16.8) ms in patients (P=0.01).

Magnetic motor conduction parameters are unaltered in schizophrenia, but transcallosal inhibition is significantly delayed and prolonged. This may indicate abnormal function of the corpus callosum in these patients.

The prevalence of mental disorders in the community is high, yet many remain unrecognised, misdiagnosed or poorly managed within primary care. Hence, guidelines for diagnosing and managing mental disorders in primary care, ICD–10 PHC, have been developed.

To introduce the guidelines into primary care and to assess whether they improve recognition, accuracy of diagnosis and treatment standards.

GPs recorded information on all patients presenting with mental disorders before and after guidelines were introduced. A10% sample of patients underwent interviews to establish a formal diagnosis. Recognition of mental disorders was assessed by screening of patients attending their GP.

The guidelines had no impact on the overall detection of mental disorders, the accuracy of diagnosis or the prescription of antidepressants. There was a significant increase in the number of patients diagnosed with depression or unexplained somatic symptoms. The GPs also made increased use of psychological interventions.

The success of the guidelines in bringing about change is by no means certain. Some areas appeared more susceptible to change than others.